Arab states, divided over how to handle the crisis in Syria, are likely to extend a peace mission there which critics say is handing President Bashar al-Assad more time to kill opponents of his rule.

Some want to crank up pressure on Assad to end a 10-month-old crackdown on a popular revolt in which, according to the United Nations, more than 5,000 people have died.

Others worry that weakening Assad could tip Syria, with its potent mix of religious and ethnic allegiances, into a deeper conflict that would destabilise the entire region, and some may fear the threat from their own populations if he were toppled.

The head of the monitoring effort, Sudanese General Mohammed al-Dabi, was in the Egyptian capital to present his report to ministers, who were due to meet after a gathering of the Arab League's Syria committee.

Hundreds of people have been killed during the monitoring mission, sent to assess Syria's implementation of the Arab plan, which was originally agreed in early November.

Syrian opposition activists said Assad's forces killed 35 civilians on Saturday and 30 unidentified corpses were found at a hospital in Idlib. The state news agency SANA said bombs killed at least 14 prisoners and two security personnel in a security vehicle in Idlib province.